Most flexible
usage & margin control for AI.

Change prices, limits, and contracts for users and agents as easily as a git commit, live.

npm i @formata/limitr

Start free How it works

Customer · The Regis Company

A Fortune 500 rollout,
unblocked.

Fortune 500

Enterprise rollout on a fixed-price contract

100,000+

Users on a single contract

3 modalities

Chat, text-to-speech, and real-time avatars

Read the customer story →

The policy

One policy file:
credits, limits, contracts.

It runs inside your app and decides every call: what's allowed, what it's worth, and what it costs you.

Edit it in Limitr Cloud, or as code.

Check each call with allow().

Change a price. It's live on the next call.

Run the quickstart

Limitr Cloud · policy editorLive

EntitlementFreeProai_tokenchatexport_pdf

policy.yamltested as written · engine 0.8.5

policy:
  credits:
    ai_token: { price: { amount: 0.00002 }, overhead_cost: 0.000008 }
  plans:
    free:
      entitlements:
        chat: { limit: { credit: ai_token, value: 50000, resets: true } }
    pro:
      entitlements:
        chat: { limit: { credit: ai_token, mode: soft, value: 2000000, resets: true } }
        export_pdf: {}   # no limit: a feature flag

app.tsengine 0.8.5

const limitr = await Limitr.new(policy, 'yaml');
await limitr.ensureCustomer('acme', 'pro');

await limitr.allow('acme', 'export_pdf');        // true
await limitr.allow('acme', 'chat', 2_100_000);  // true, soft limit
// event: meter-overage → bill acme: $2

outputallow('acme', 'export_pdf') → trueallow('acme', 'chat', 2_100_000) → trueevent: meter-overage → bill acme: $2.00

The engine

Built so you
never rip it out.

New pricing, products, or business model? It's a policy change, not a migration. Open source and built on Stof, so it bends to your business forever. It runs inside your app, offline and sandboxed.

View on GitHub

How the engine works →

Control

Feature flags, hard and soft limits, spend caps, an agent's budget.

allow('ada', 'chat', 60_000) // false

Bill

Usage pricing, credits, overage, one customer's contract. Margin known per call.

meter-overage → bill acme: $2

Limitr Cloud

Ship pricing like
a git commit.

In Limitr, pricing is one versioned policy. Change it, diff it, test it on real traffic, ship it to every engine, and roll it back in a click. No ticket, no release.

Start free Pricing

Policy · draftChanges

Draft · 2 changesPriya · just now

pro · chat2M tokens→3M tokens

ai_token · price$20 / 1M→$22 / 1M

MessageRaise Pro chat to 3M, reprice tokens to $22

Test · last 30 daysnot run

Replays real calls through the draft before anyone sees it.

LiveDraftRevenue / month$52,400$55,580Margin41%44%Customers paying more—38 of 1,204Hit a new limit—none

v24Every engine gets it on the next call when you publish.api-usapi-euworker

Limitr Cloud · made-up workspace and numbers

Ledger to invoice

Usage lands in a ledger and rolls into invoices. Stripe built in, or your own rails.

Limitr Analyst

The agent in Cloud. Ask what a change will do, it simulates it on real usage, then writes it.

Agentic by design

Built for coding agents.

Limitr ships with skills, so your coding agent knows the policy, the SDK, and the patterns, and does the integration for you.

/plugin marketplace add dev-formata-io/limitr

/plugin install limitr@limitr

Write the policy

Credits, plans, limits, prices, one customer's contract, from a plain brief. Tested before it ships.

Wire the SDK

allow() at the call, reserve and settle around the model, events to your billing, in your framework.

Build the surfaces

Usage views, plan pickers, billing settings, and internal controls in your own UI, read from the policy.

Answer the hard questions

Margin per customer, what a price change would do, where a cap should sit, from the engine's own events.

Start free. Scale with usage.

Full pricing →

Open source

Free

The engine, forever. Write and test policies in Cloud.

Start free

Pay as you go

$49 /mo

Publish live. Ledger, invoices, Stripe.

Go live

Scale

$499 /mo

Custom deals, contracts, forecasting.

Start on Scale

Enterprise

Let's talk

Usage included, SLA, our team.

Book a demo

Make usage profitable.